bonding: Convert memcpy(foo, bar, ETH_ALEN) to ether_addr_copy(foo, bar)

ether_addr_copy is smaller and faster for some architectures.

This relies on a stack frame being at least __aligned(2)
for one use of an Ethernet address on the stack.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>